Key operated lock mechanism



Jan. 3, 1956 J. w. TAYLOR 2,729,091

KEY OPERATED LOCK MECHANISM Filed Feb. 18, 1952 3 Sheets-Sheet 1 INVENTOR JACK W. TAYLOR A TTORNE Y Jan. 3, 1956 J. w. TAYLOR KEY OPERATED LOOK MECHANISM 3 Sheets-Sheet 2 Filed Feb. 18, 1952 INVENTOR JACK w. TA YLOR A TTORNE Y 1955 J. w. TAYLOR 2,729,091

KEY OPERATED LOCK MECHANISM Filed Feb. 18, 1952 3 Sheets-Sheet 3 INVENTOR J'ACK W. TA V1. 08

ATTORNEY '2 ,729, 091 KEY OPERATED LOCK MECHANISM Jack William Taylor, New'De'nhani; Eiigland; assigtio'r'to lngersoll Limited; London, England Application February 18, 1952, Serial'Noi 271,992

Claims priority; application GreafiBritain February 19,1951

Thisinvention relates 'to k'ey'o'perated lock mechanism andis particularly concerned with plug and cylinder type lock mechanism incorporating a'series' of tumblers or equivalent members which are movedas a result 'of .in-

sertion 'of the appropriate key to permit rotation of the plug within its associated cylinder.

In the case of plug'a'nd' cylinder type lock mechanism as at present constructed where it is desired to operate the lock from both sides of thedoor; it is' the practice to'fit two such cylinders one on theinside and 'one'ori the outside of the door. Such an'arrarigement has'thedisadvantage of adding considerably to the cost, whilst the cylinders project from the faces of the do'or'to such an extent as to render them unsightly and has *the further disadvantage thatgrips can be appliedto the" projecting parts to forcibly rotate the complete "mechanism and thereby to operatethe lock without using ak'ey.

Furthermore in cases where front'and'rear entry of "the key was possible the number of key changes was reduced to such adegree as" to render the key mechanism virtually useless for security purposes.

Thechief object of the present invention is to evolve a key operated lock mechanism and particularly key operated mechanism of theplugand cylinder 'type' which can be associated with alock that the cylinder does not "project unduly from'either side of the demand atthe -sarne tiniecan be operated from'either'inside or outside, "preferably through the medium of the same key,the'cylinder being of substantially the same lengthas themore 1 usual cylinder in whichthe plug is operable from one side only. 7 a

Key operated 'lock mechanismin accordance with the present inventionincludes two 'key"holes' or key "slots enterable from opposite sides'of the 'lock mec'hanism, the key slots being-laterally spacedapart anamo'unt such that the key when inserted from'either side"ofthefdoor will contact and operate the same set'of tuinblerso'r other operating components.

' The advantages gained with the inventiondo' notreduce the 'key changes atall, on the contrary they" may even be increased. 7

In the case of plug and cylinder lockmechaiiism the key holes will be-disposed laterallyon' opposite'sides' of the axis of-rotation of'the plug, the'plug and cylinder being'of more or less normal'length as used for operation from one endonly. his preferred that the "key slots shall not extend completely through-the plug sothatonly one key slot-will be observablefrom eachend, but if from the point of view of manufacture it is f ound"easier to cut the slots completely through the plug the-end of each slot remote from the entrance is preferably so shaped as to prevent entry of a-key from that 'end.' Furthermore, although it is contemplated that 'two slotswill actually be used these slots may; in fact,--be combined but will provide two key passages of identical cross sectional shape. p

-In order-thatthe invention may be clearly understood and readily carried into effect the invention'is' hereinafter 2,729,091 Patented-Jan. 3, 1956 2 described with reference tofthe' accompanying drawings 'inwliich: I V

Figures 1 and 2 are views in elevation or a'plug and cylinder lock-mechanism having-two laterally arranged key slots; the views being taken'from' the front and rear of the mechanism respectively; p

Figure 3 is across-sectional view corresp'o'ndingtd line 3-3 of Figure 1 and showing a-key'inserted in one'ofthe key "slots-"from one side of thelock mechanism;

Figure 4 is acros's seetional view corresponding to line 4+4of Figure Z'a'ndsh'oWing a key inserted in the other 'key' 'slot'fromt'he opposite side-of the lo'ckmechanism;

' Figure S'is a-cros's-s'ectional'view corresponding to line 5-5 of Figure 3 'aridshowing a-tumbler or one set in locking position;

Figure 6 is across-sectional view corresponding to line 66'of Figure 3"and showing a'tuinbler of the other set' in locking 'p'os'ition;

Figure 7 is across-sectional view similar-to Figure 6 but showing the key inserted, -as shown in Figure 3, and

the tumbler in 'uiilocked position;

' Figure 8 is a cross-sectional view similar to Figure 5 but showing the key-inserted, as in Figure 7, and the tumbler in unlocked position;

'Figure 9'is a cro's's-sectionalview similarto Figure 7 l and showing the plug-inpartialrotation within the. cylinde'r 'to'u'nlock' or 'release the lock mechanism;

Figure "10 is a cross-sectional view transversely through ainodified lock mechanism embodying pivoted tumblers;

Figure 11 is a cros's sectionakview longitudinally through a modified lock mechanism embodying pin "tumblers; V

Figure 12 is a cross-sectional view of-Fi'gure 11; Figure 13' is a cross-sectional view similar to Figure 12 Wt showing only'on'eset ofpiii'fumblers;

Figure" 14 is across-sectional view-similar to Figures 12' and 13 but showing in'odified pin tumblers;

Figure" 15' is a cross-sectional view longitudinally through anothermodification'of the lock mechanism;

Figure 16' is a diagrammatic cross sectional view correspondin to line 16'16of Figure 15;

Figure 17 is a diagrammatic view of a constructional "feature"of the lo'ckinechaiiism' shown in Figures-5-9 "and16;

4 'Figu're'18'is across-sectional view transversely through aplug' and illustrating one arrangement of the key slots;

'Fignre'19'is across-sectional'view similar to Figure 18 and illustrating another arrangement of the keyslots;

FigureZO is a cross-sectional view corresponding to line -21 'j21of"Figure '19; and

Fiure 22 is'a cross-sectional view similar to Figures 20"and '2l"and illustrating a modified'form of locking the Figure 21 is a cross s'e'ctional view corresponding to 55 "inoperative endso'f the'k'ey slots.

Referring in the first case'to'Figures 1 to- 9 of the "accoinpanying*drawingsfthe lock mechanism includes a cylinder 1 containing a' 'rotatably mounted plug 2 the plug being formed with t'wokey slots Sand 4 which are laterally spaced onopposite sides'of the plugs axis of periphery.

Each tumbler'is'foi'med with a central opening through which-the key 7 can passfthekey being'of asymmetrical cross-Sectional shape andbeing' notched or serrated on both edges, this asymmetrical cross sectional shape preventing the key being inserted into the key slot upside down.

The edges of the key are serrated or notched to a depth which will impart the necessary lift to all the tumblers as a result of introduction of the key into the plug as to permit of rotation of the plug within the cylinder under the controlling turning movement of the key so as to actuate the lock and it will be appreciated that the depth of the notches or serrations on opposite sides will provide the desired combination.

Each tumbler 6 is formed with a peripheral notch 8 and normally these notches will be out of alignment, the tumblers normally occupying the positions shown in Figures 5 and 6, Figure 5 showing a tumbler which is movable upwardly whilst Figure 6 illustrates a tumbler which is movable by the key in the opposite direction. The tumblers are normally maintained in the positions shown in Figures 5 and 6 by means of blade springs 9.

The plug carries a pivoted talon 10, the outer extremity of which enters a recess 11 formed in the inner surface of the cylinder and thus prevents rotation of the plug within the cylinder when the tumblers are in the position shown in Figures 5 and 6. On the tumblers being given the requisite lift by the insertion of the appropriate key they will be moved into the position shown in Figures 7 and 8 where the notches 8 are all in alignment and in this position the opposite or inner end of the talon is free to enter the notches 8 and the outer end to move clear of the recess 11 of the cylinder. If the key is given a slight preliminary movement the plug will be turned slightly in the cylinder in which case the walls of the recess 11 will earn the talon into a position in which it enters the aligned notches and is moved clear of the recess 11, thus permitting continued rotational movement of the plug to actuate the lock.

Assuming that the key and plug have to be turned through 360 to actuate the lock, the talon will return to the position shown in Figures 7 and 8 and to release the talon from the aligned notches and permit withdrawal of the key, a spring 16 may be associated with the talon, as shown in Figure 16, which will cause the latter to return into engagement with the recess 11. Alternatively the talon may engage a suitable cam track 17 in the cylinder such as is shown in Figure 17.

In order that the tumblers will be given the correct lift irrespective of the direction of entry of the key into the plug, the inner key engaging edge of each tumbler is formed with two faces 12 which are stepped relative to one another, the step being of a particular depth to suit the particular combination chosen.

In Figure a modified form of lever tumbler is shown, which tumbler 6a, although still movable in an arcuate path within the recess 5a within the plug 2a, nevertheless is pivotable about the fulcrum carried by the plug 2a. In this case each tumbler is formed with two peripheral projections 10a and 10a which enter grooves or recesses 11a and 11a in the cylinder 1a these grooves and projections being preferably of the undercut or dovetail formation shown. The springs 9a normally hold the tumblers in the position shown in which all the projections 10a are in engagement with their adjacent recess. On the key being inserted in the respective key slot 3 or 4, and presuming it is the correct key which will engage the tumbler edges 12a to impart the correct amount of lift to all the tumblers, the projections 10a will be moved clear of the recess 11a thus permitting the plug to turn in the cylinder. If the lift, however, is abnormally large the opposite projection 10a will enter the recess 11a thus still preventing turning movement. It is essential, therefore, that the lift imparted to the tumblers shall be no less and no more than that for which the key mechanism is designed thus making for greater security. As there will be two sets of tumblers movable in opposite directions the dovetail shape of the projections and recesses will tend to cause the parts to engage further if an attempt is made to turn the plug forcibly in either direction by means other than the correct key.

In Figures 11 to 14 the invention is shown applied to a plug and cylinder lock mechanism of the pin tumbler type and as the plug is again formed with two key slots which are laterally spaced on opposite sides of the plugs axis of rotation, it is necessary to arrange the pin tumblers in laterally connected pairs or dual pin tumblers. Figures 11 and 12 show two diametrically disposed sets of fixed pairs of pin tumblers, Figure 13 shows only one set of connected pairs of pin tumblers, and Figure 14 shows pin tumblers spanning both key slots and having dual key engaging edges.

Referring to Figures 11 and 12, the lock mechanism comprises a cylinder 1b within which the plug 2b is mounted and provided with key slots 3 and 4. The plug is provided with recesses 0r slots 5b and the cylinder with recesses or slots 11b within which the pairs of pins 6b having key engaging ends and drivers 16b of the pin tumblers are slidably mounted and biased by springs 9b. The structure shown in Figure 13 is identical except that the cylinder 1b and plug 2b accommodate only one set of the dual or pairs of pin tumblers.

The pin tumblers of each pair are respectively aligned with the two key slots 3 and 4 and are connected together so that they will be moved jointly when a key is inserted in either of the key slots. It is more convenient from the point of view of obtaining a particular combination to construct the pin tumblers separately and to connect them together in pairs, by what might be termed a pin and slot connection, so that they will be moved jointly by introduction of the key into the plug from either end and will be given a lift appropriate to free the plug and permit of its rotation within the cylinder.

On the other hand, it is more convenient from the point of view of manufacture and assembly to form the dual pin tumblers integrally and this structure is shown in Figure 14 wherein pins 6b and drivers 10b are slidable in slots or recesses 5b in the plug 2b" and slots or recesses 11b in the cylinder 1b", the pin tumblers being biased by a spring 912. The pins 6b have dual key engaging edges and span both key slots 3 and 4 of the plug. The pin 6b may be of any suitable cross-sectional shape, such as for example, square or hexagonal and is of the stepped formation shown in the illustration.

Referring now to Figures 15 and 16, a more simple type of lever tumbler mechanism is shown, each tumbler 60 being pivoted at within the slots 50 in the plug 20 and having associated with it a suitable blade spring 9c; the tumblers being notched as at 8 for the entry of a talon 10 pivotally associated with the plug, the cylinder 1c being again formed with a recess 11 in its inner surface for the entry of the talon therein to prevent rotation of the plug within the cylinder until all the tumblers have been moved into the position shown in Figure 16 by the insertion of the appropriate key in which position all the notches 8 are aligned, entry of the talon into the notches 8 being brought about by initial turning movement as described in connection with Figures 5 to 9. Re-entry of the talon into the recess 11 at the termination of turning movement of the key is brought about by means of a spring 16 (Figure 16) or a cam track 17 (Figure 17) in the end of the cylinder with which cam track a projection 18 on the talon engages, the cam track being formed with an operative part 19 which brings about the said re-engagement of the talon in the recess 11.

It will be observed that the previously described figures illustrate alternative ways in which the two laterally positioned key holes may be formed in a plug and these modifications are more particularly shown in Figures 18 to 22. In Figures 18 and 20, a single slot is formed which provides two key passages 3 and 4 which are laterally positioned in a plug 2. In Figures 19 and 21 two key slots 3" and 4" are provided in a plug 2". Figures 20 or 21 and 22 illustrate two alternative ways in which introduction of the key into both slots from both ends of the plug is effectively prevented. In Figures 20 and 21 the slots do not project throughout the full length of the plug. In Figure 22 the slots project completely through the plug, but the end opposite to the mouth is reduced in width as at 24 for the purpose of preventing key entry from that end.

I claim:

1. Key operated lock mechanismcomprising a cylinder having a bore, a plug revolvably mounted in the bore of said cylinder, pin tumblers movably mounted in said plug, said plug having two laterally spaced key slots extending longitudinally thereof, said pin tumblers comprising two similar sets respectively disposed on opposite sides of the axis of the lock mechanism and jointly spanning both of said key slots for cooperation with a double edge key and having key engaging surfaces cooperating with a key in either of said slots, said key slots having key receiving openings respectively at opposite ends of said plug, and means under the control of said pin tumblers for preventing rotation of said plug within said cylinder until all of said pin tumblers have been moved the correct amount, whereby the proper key may be inserted in either of said slots for moving said pin tumblers to release said means and permit rotation of said plug within said cylinder.

2. Key operated lock mechanism as defined in claim 1, wherein the ends of said key slots opposite said key receiving openings being at least partially closed to prevent insertion of a key in each slot from both ends of said plug.

3. Key operated lock mechanism as defined in claim 1, wherein said plug has integrally fixed projections to at least partially close said key slots opposite said key receiving openings to prevent insertion of a key in each slot from both ends of said plug.

4. Key operated lock mechanism as set forth in claim 1, wherein the tumbler key engaging surfaces being stepped to provide the required movement by the key in either of said slots.

References Cited in the file of this patent UNITED STATES PATENTS 91,733 Fowler et al June 22, 1869 121,142 Warren Nov. 21, 1871 446,192 Sargent et al. Feb. 10, 1891 588,026 Stadtmuller Aug. 10, 1897 1,095,500 Hansen May 5, 1914 1,860,708 Falk May 31, 1932 2,111,515 Rauh Mar. 15, 1938 2,524,339 Young et a1. Oct. 3, 1950 2,641,125 Orquieta June 9, 1953 FOREIGN PATENTS 927,457 France May 5, 1947 982,349 France Jan. 24, 1951 993,764 France July 25, 1951 

